The protein chemistry section of the core will serve as a central resource of expertise and equipment for program projects which have as a goal the isolation and characterization of new growth factors (differentiation factors) or other proteins of interest. The protein chemistry core will provide support in the preliminary studies concerning the stability and general properties of each of the novel proteins as well as throughout the development of successful purification procedures. The facility will play a major role in characterizing all purified factors. Particularly important will be the protein microsequencing service available in this core laboratory. State of the art technology will high sensitivity (picomole level) amino acid analysis (HPLC) and automatic gas phase and manual batchwise amino acid sequence analysis. Special emphasis will be placed upon integrating individual project goals with the technical advantages available through molecular biology. To this end, the protein chemistry facility will assist with selective purification of peptides suitable for the design and synthesis of oligonucleotide hybrization probes by the recombinant DNA laboratory. In addition, appropriate attention will be given to identification of sites of co- or post-translational modifications such as disulfide bridges, glycoslyation and phosphorylation. The protein chemistry facility will also provide an automated peptide synthesis service, allowing for yet another approach to structure-function studies of proteins.